6W18

Structure of S. pombe Arp2/3 complex in inactive state

ELECTRON MICROSCOPY

Refinement

RMS Deviations
Key	Refinement Restraint Deviation
f_dihedral_angle_d	19.484
f_angle_d	0.5135
f_chiral_restr	0.0408
f_bond_d	0.0025
f_plane_restr	0.0018

Sample
Arp2/3 complex

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	HOMEMADE PLUNGER
Cryogen Name	ETHANE
Sample Vitrification Details	4 uL of sample was applied to freshly glow-discharged grid. Excess sample was manually blotted off with a dry Whatman No.1 filter paper for 5-7 second ...	4 uL of sample was applied to freshly glow-discharged grid. Excess sample was manually blotted off with a dry Whatman No.1 filter paper for 5-7 seconds. Immediately after the blotting step the sample containing grid was rapidly vitrified by plunge freezing into liquid ethane.

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	112170
Reported Resolution (Å)	4.2
Resolution Method	FSC 0.143 CUT-OFF
Other Details
Refinement Type
Symmetry Type	POINT
Point Symmetry	C1

Map-Model Fitting and Refinement
Id	1 (3DWL)
Refinement Space	REAL
Refinement Protocol	FLEXIBLE FIT
Refinement Target
Overall B Value
Fitting Procedure
Details

Data Acquisition
Detector Type	FEI FALCON III (4k x 4k)
Electron Dose (electrons/Å**2)	44.34

Imaging Experiment	1
Date of Experiment
Temperature (Kelvin)
Microscope Model	FEI TALOS ARCTICA
Minimum Defocus (nm)	-700
Maximum Defocus (nm)	-1300
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS	2.7
Imaging Mode	BRIGHT FIELD
Specimen Holder Model	FEI TITAN KRIOS AUTOGRID HOLDER
Nominal Magnification	120000
Calibrated Magnification
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	200
Imaging Details	Data were collected by combining untilted and tilted (20, 30 and 40 degrees) images. Stage shifting to the targeted exposure position was used for navigation during data acquisition.

EM Software
Task	Software Package	Version
PARTICLE SELECTION	cryoSPARC	2.12.4
IMAGE ACQUISITION	EPU	2.2.0.65
CTF CORRECTION	cryoSPARC	2.12.4
MODEL FITTING	NAMD
MODEL FITTING	Coot
MODEL FITTING	UCSF Chimera
FINAL EULER ASSIGNMENT	cryoSPARC	2.12.4
CLASSIFICATION	cryoSPARC	2.12.4
RECONSTRUCTION	cryoSPARC	2.12.4
MODEL REFINEMENT	PHENIX

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
PHASE FLIPPING AND AMPLITUDE CORRECTION	Local CTF estimation was performed for all micrographs using the CTF estimation package within cryoSPARC.	3336981	Automated Gaussian-based blob picker was used.

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.